Change calcGPSValidity() to isGPSGroundTrackValid(). Replace existing isGPSGroundTrackValid() function.

main/gps.go

@@ -1994,7 +1994,7 @@ If false, 'GPSFixQuality` is set to 0 ("No fix"), as is the number of satellites
 
 func isGPSValid() bool {
 	isValid := false
-	if (stratuxClock.Since(mySituation.GPSLastFixLocalTime) < 15*time.Second) && globalStatus.GPS_connected && mySituation.GPSFixQuality > 0 {
+	if (stratuxClock.Since(mySituation.GPSLastFixLocalTime) < 3*time.Second) && globalStatus.GPS_connected && mySituation.GPSFixQuality > 0 {
 		isValid = true
 	} else {
 		mySituation.GPSFixQuality = 0
@@ -2006,8 +2006,14 @@ func isGPSValid() bool {
 	return isValid
 }
 
+/*
+isGPSGroundTrackValid returns true only if a valid ground track was obtained in the last 3 seconds,
+and if NACp >= 9.
+*/
+
 func isGPSGroundTrackValid() bool {
-	return stratuxClock.Since(mySituation.GPSLastGroundTrackTime) < 15*time.Second
+	return isGPSValid() &&
+		(mySituation.GPSHorizontalAccuracy >= 30)
 }
 
 func isGPSClockValid() bool {

main/sensors.go

@@ -236,7 +236,7 @@ func sensorAttitudeSender() {
 			}
 
 			m.TW = float64(mySituation.GPSLastGroundTrackTime.UnixNano()/1000) / 1e6
-			m.WValid = calcGPSValidity()
+			m.WValid = isGPSGroundTrackValid()
 			if m.WValid {
 				m.W1 = mySituation.GPSGroundSpeed * math.Sin(float64(mySituation.GPSTrueCourse)*ahrs.Deg)
 				m.W2 = mySituation.GPSGroundSpeed * math.Cos(float64(mySituation.GPSTrueCourse)*ahrs.Deg)
@@ -329,11 +329,6 @@ func updateExtraLogging() {
 	logMap["BaroVerticalSpeed"] = float64(mySituation.BaroVerticalSpeed)
 }
 
-func calcGPSValidity() bool {
-	return (stratuxClock.Time.Sub(mySituation.GPSLastGroundTrackTime) < 3000*time.Millisecond) &&
-		(mySituation.GPSNACp >= 9)
-}
-
 func makeSensorRotationMatrix(g [3]float64) (rotmat *[3][3]float64) {
 	f := globalSettings.IMUMapping
 	if globalSettings.IMUMapping[0] == 0 { // if unset, default to some standard orientation
@@ -419,8 +414,8 @@ func updateAHRSStatus() {
 		<-ticker.C
 		msg = 0
 
-		// GPS valid
-		if calcGPSValidity() {
+		// GPS ground track valid?
+		if isGPSGroundTrackValid() {
 			msg++
 		}
 		// IMU is being used